Summary: Researchers find that caregivers who talk and respond to their infants boost language development. This benefit applies to all children, including those later diagnosed with autism spectrum disorder (ASD).
Source: UT Dallas
New research shows that increased caregiver speech and conversational interaction in infancy supports later language skills for children both with and without autism.
Dr. Meghan Swanson, an assistant professor at The University of Texas at Dallas and the corresponding author of the study published online June 28 in Autism Research, led a project that extends prior work linking caregiver speech to language outcomes in typically developing children to infants who are later diagnosed with autism. The findings point to practical steps families and clinicians can take to support early communication and may inform recommendations for intervention when developmental concerns arise.
“Autism can be diagnosed reliably at 24 months, but many children are identified later,” Swanson said. “Evidence shows that intervention between birth and age three can be especially effective. So demonstrating that everyday caregiver behaviors support language development — even for infants who will later receive an ASD diagnosis — is important for guiding early support.”
The study followed 96 infants from 9 months to 24 months. Sixty of the infants had an older sibling with autism, a “baby-sibling” design that enriches the sample for autism risk. Because autism runs in families, younger siblings of autistic children have a higher probability of receiving a diagnosis themselves; in this study 14 of those high-risk infants were diagnosed with autism at 24 months.
Researchers used all-day home audio recordings at 9 and 15 months to measure the quality of each child’s language environment. Recordings were analyzed with LENA (Language ENvironment Analysis) software, which counts adult words and conversational turns — each instance in which an adult vocalizes and an infant responds or vice versa. Children’s language skills were evaluated at 24 months.
Across the entire sample, infants who heard more adult words and experienced more conversational turns at 9 and 15 months scored higher on language assessments at 24 months. This association held true for infants who later received an ASD diagnosis as well as for typically developing infants.
“One clear takeaway is that caregivers should continue to talk and respond to their babies, even if the infant does not respond consistently,” Swanson said. “These responsive back-and-forths appear to support language growth regardless of later diagnostic status.”
The researchers also found that higher parental education was linked to a richer home language environment, and mediation analyses indicated that this relationship partly explained differences in children’s language outcomes. Exploratory analyses revealed that typically developing infants showed an increase in caregiver–child conversational turns between 9 and 15 months; this developmental increase was not seen in infants later diagnosed with ASD.
Swanson emphasized the value of longitudinal research that follows the same children over time. “To understand development, you need to track the same individuals across months and years,” she said. “Cross-sectional snapshots of different age groups can miss important patterns.”
She also addressed historical misconceptions that unfairly blamed parents for causing autism. “Some families worry about what they might have done differently,” Swanson said. “There is no scientific evidence that parenting style causes autism. At the same time, parents can be powerful agents of positive change by creating rich communication opportunities for their infants.”
The project was part of the Infant Brain Imaging Study (IBIS) network, a consortium of eight universities in the U.S. and Canada funded as an Autism Center of Excellence by the National Institutes of Health. Sites contributing data included the University of North Carolina at Chapel Hill, Children’s Hospital of Philadelphia, Washington University in St. Louis, the University of Washington, and the University of Minnesota, among others. Swanson conducted this work while completing postdoctoral research at UNC–Chapel Hill.
Dr. Joseph Piven, the IBIS network principal investigator and director of the Carolina Institute for Developmental Disabilities at UNC–Chapel Hill, highlighted the practical implications for families. “Talking with and responding to your child from an early age can shape language skills that influence many later abilities,” he said. “Supporting early language development increases the chances for broader academic and social success.”
Swanson summarized the study’s most encouraging message: parents can make a tangible difference in their children’s early language trajectories. “From as early as nine months, caregivers who provide a rich communication environment help support their children’s development,” she said. “That’s an empowering and hopeful conclusion for families and professionals working to foster healthy language growth.”
In addition to UT Dallas and the IBIS sites, investigators from Temple University, the Perelman School of Medicine at the University of Pennsylvania, McGill University, and the University of Alberta contributed to the research. The Simons Foundation also provided support.
Source:
UT Dallas
Media Contacts:
Stephen Fontenot – UT Dallas
Image Source:
Image credit: UT Dallas/Chris Adam.
Original Research: Closed access
Title: “Early language exposure supports later language skills in infants with and without autism.” Meghan Swanson et al.
Autism Research (DOI: 10.1002/aur.2163)
Abstract
Early language exposure supports later language skills in infants with and without autism
This longitudinal study examined whether caregiver speech and conversational interactions in infancy predict later language outcomes for children who are and are not later diagnosed with autism spectrum disorder (ASD). Researchers compared three groups: high‑familial‑risk infants who did not develop ASD (n = 46); high‑familial‑risk infants who developed ASD (n = 14); and low‑familial‑risk typically developing infants (n = 36). All‑day home audio recordings were collected at 9 and 15 months and language assessments were administered at 24 months. Across groups, a richer home language environment — reflected in more adult words and more conversational turns — at 9 and 15 months was associated with better language skills at 24 months. Parental education correlated with a richer language environment, and mediation analyses suggested that the home language environment explained the influence of education on child language outcomes. Exploratory results indicated that typically developing infants experienced an increase in conversational turns from 9 to 15 months, a pattern not observed in infants who later developed ASD. These findings highlight the potential for early caregiver behaviors to support language development in infants, including those at risk for or later diagnosed with ASD.